Elucidating the elusive crystal structure of 2,4,6-tris(2-pyrimidyl)-1,3,5-triazine

Abstract

2,4,6-Tris(2-pyrimidyl)-1,3,5-triazine (TPymT) has been synthesized using two approaches: via trimerization of 2-cyanopyrimidine at 160 °C and by the reaction of 2-cyanopyrimidine with pyrimidine-2-carboximidamide. It was found that the two different synthetic pathways to TPymT yielded either a single polymorph or a mixture of two polymorphs; both of which were studied for the first time by X-ray powder diffraction (XRPD) and synchrotron X-ray powder diffraction (SXRPD). The crystal structure of the polymorph α-TPymT was determined by single crystal X-ray diffraction (SCXRD). Crystal structures of 2-cyanopyrimidine and pyrimidine-2-carboximidamide were also elucidated by SXRPD.